Vapor-liquid contact assemblies



Jan- 19, 19 0 P. s. HEPP 2,921,777

VAPOR-LIQUID CONTACT ASSEMBLIES Filed June 1. 1956 4 Sheets-Sheet 1 Fig.HEW

PET S. P

Q/WSW ATTORNEY Jan. 19, 1960 P. s. HEPP 2,921,777

VAPOR-LIQUID CONTACT ASSEMBLIES Filed June 1, 1956 4 Sheets-Sheet 2 INVEN TOR. PETER S. HEPP 'Q ZXW-b. W

ATTORNEY Jan. 19, 1960 P. s. HEPP 2,921,777

VAPOR-LIQUID CONTACT ASSEMBLIES Filed June 1, 1956 4 Sheets-Sheet 3INVENTOR. PETER S. HEPP Qua sww ATTORNEY Jan. 19, 1960 p 5 51:

VAPOR-LIQUID CONTACT ASSEMBLIES 4 Sheets-Sheet 4 Filed June 1, 1956INVENTOR.

PETER S. HEPP ATTORNEY United States Patent 2,921,777 I vAPoR-U UmCONTACT ASSEMBLlES Peter S. Hepp, Springfield, P a., assigi1or to SunOil Company, Philadelphia, Pa., a corporation of New Jersey ApplicationJune 1, 1956, Serial No. 588,879 3 Claims. or. 261-114) This inventionrelates to improvements in vapor-liquid contact assemblies, such as areused in fractionating towers and similar structures designed for thepurpose of intimately contacting or separating gas and liquid.

Presently a normal arrangement for vapor-liquid contact assemblies infractionating towers requires spacing trays of difierent contact devicesat selected vertical levels.

For example, one tray will support the well known bubble caps ofacceptable design above openings as by chimneys, cooperatively engagingthese openings. This special type of equipment may be repeated or may beinterspersed with other contacting elements designed to assist inobtaining the desired results. In any case the flow of gas upwardly inthe tower comes in contact with descending liquids and by means of theseparate elements these are caused to more intimately contact orseparate. Additional equipment used with bubble cap trays frequentlytakes the form of an element or group of elements positioned to becarried on the under side of the opening in the tray over which thebubble cap is' mounted. An example is found in bubble caps combined withsuspended inverted cups. Interposed layers of mist-eliminating materialplaced in the space between bubble cap trays is frequently used in placeof such inverted cups, serving generally the same purposes. In such acase, as this last-mentioned expedient, the cost and labor required ininitial installation and later maintenance of such an added device canbe economically excessive. It is an object of this invention to providea vapor-liquid contact assembly which will serve the full purpose oftray supported bubble caps interspersed with additional contact orseparating elements, at greatly reduced cost and labor expense both ininitial installation and maintenance.

A further object of this invention is to provide separatemist-eliminating elements adapted to cooperate with separate bubblecaps.

Another object is to provide a mist-eliminating element, chimney andbubble cap combination as a vaporliquid contact assembly designed forinstallation and maintenance by a single workman working from one sideof the supporting tray only and without need of a helper.

Yet another object is to provide a vapor-liquid contact assembly of thestated elements which, although firmly engaged against dislodgingpressures and surges within the tower, are easily and quickly releasedfrom either side ofthe supporting tray without the need of specialtools.

Still another object is to provide a bubble cap-chimney combination fornormal use which providesan easily ice 2 in connection with theaccompanyir'igdrawings, in which: Figure 1 is a side elevation of theupper part of a tower in sectional view showing the improved assembl inoperating arrangement. I

Figure 1A is a side elevation of the intermediate and lower portions ofa tower partially broken away in which is shown an alternate arrangementof the invention.

Figure 2 is a sectional view of Figure 1 taken on line 22.

Figure 3 is a sectional view of Figure 1A taken on line 3-3.

Figure 4 is a vertical sectional View of the bubble capdemistercombination assembled in operating position and enlarged to showstructural detail.

Figure 5 is a sectional view of Figure 4 along line 5-5 showing latchedand unlatched positions.

Figure 6 is an exploded vertical view in section showing the separateelements in position for engagement or removal.

Figure 7 is an elevational view in section of a modification of oneelement of the combination adapted for use in existing installations,completing the combination with a phantom outline of the existingportion.

Figure 8 is a sectional view of Figure 7 taken on line 88.

Figure 9 is an elevational view in section of an alternate arrangementof the modification illustrated in Figure 7.

Figure 10 is an elevational view in section of another alternatearrangement of the device illustrated in Figure 9.

Figure 11 is a bottom view of the device shown i Figure 10. J

Referring to the details of the drawing, there is illustrated the usualtype of fractionating tower or column 10, Figures 1 and 1A, which may beprovided with inlets and outlets as are required, and here indicated. Anumber of transverse trays 12 in Figure 1 and 14 in Figure 1A aresupported on the wall of the tower casing. Liquid is permitted to passdownwardly from one tray to another through the usual overflow pipes 16,or otherwise.

The vapor passages are provided with chimneys secured to the trays 12,14. To facilitate the assembly and disassembly of the elementsassociated with these chimneys, later to be described, the chimney,shown as part of this combination, assumes a special configuration alsolater described. Several forms of the element for use with existingchimneys as shown in Figure 1 are also described as modifications of onepart of this combination.

Continuing the general description, the two trays 12 and 14 indicated inFigures 1 and 1A are included to show two arrangements of the flexibleassembly possible with the vapor-liquid contact device of thiscombination.

Figure 2 illustrates the use of demister body 21 fitting tightly againstthe underside of tray 12 to cover the chimney opening. Such anarrangement as this permits easy installation of the demister body,otherwise suspended in a separate tray, and eflicient replacement ofdefective areas where necessary. As thus assembled and operated, thechimney opening is covered by the demister body 21 which can be reducedin area to any economical proportions required by the chimney area. Theterm demister body used above and later in this specification, refers toa piece of filter body material such as is described and claimed inPatent No. 2,327,184, or the like, especially manufactured for thepurpose of intercepting gas entrained liquid particles.

Figures 1A and 3 show a spaced relation between the demister body 20 andthe underside of tray 14. When this spaced relation is used, closelyapproaching present practices of suspended demister masses,- closeassociation nized that the chimney spacin attern will determine the mostsatisfactory polygon shape to assume to obtain a continuous demisterbarrier below the chimneys. As indicated, the suspended demister forms20 contact each other and extend across the critical portion of thetower.

As later to be described, the fiexioility of the several disclosedelements affords variable vertical and horizontal spacing as well asease in maintenance and installation,

for better production. The suspended demister body can be used with animpervious collar or vertical spacer as it is called, which can beconsidered as a continuation of the chimney structure supported by thetray supplying an additional flue for gases and liquids, or the spacermay be made of demister or other porous material avoiding therequirement for matching geometrical patterns by extending the activedemister area. This is disclosed and discussed in reference to figuresof the drawing described later.

In any of the forms indicated, however, the vapor-liquid contactfunction of the disclosed combination is the same, and it retains allthe necessary flexibility to meet the stated objects and above operatingdescription. Figures 4, 5 and 6 are referred to for an understanding ofthe elements of this assembly each cooperating with the other tocomplete the combination.

In the specific combination disclosed here and illustrated in theseFigures 4 to 6, inclusive, the common support for both the bubble cap 19above the tray and the separator body (called demister here and numbered29 or 21 as shownabove) below the tray, is the chimney 18. For thiscombination, the chimney is especially designed and, as is evident fromFigures 4 and 5, is cylindrical in section with smooth areas 22 spacedapart, circumferentially, on the inner wall. Cut into the inside of thechimney 18 between these smooth areas 22 are grooved areas formed of aplurality of horizontal grooves 24 arranged in parallel at predeterminedelevations. These afford elevational positioning means for the separatoror demister bodies 20 or21 relative to the mounting tray and latchingarrangements for the bubble caps, aswill be better understood later. Byspacing smooth areas in the chimney asat portions 22, between thelatching segments 24, both the cap and separator body or demister can bequickly clipped in operating engagement or removed by a slight twistpreliminary to the lift or drop required. It will be evident that thisspecial chimney may be combined with the described bubble cap as asub-combination of the complete assembly, or used to support thedemister element with other forms of bubble caps. A modified form of thedemister element subcombination makes it usable also with other types ofbubble caps and chimneys as later described.

A spring clip 26 extends upwardly through the demister material atsubstantially third points forming an operating element of thissub-combination. structurally this corresponds to the circumferentialspacing of the grooved portions 24 of the chimney 18 described above.

A grip 28 attached to clip 26 assists in placing and re-- inserted toproper level then turned into locking engage ment in the selectedgrooves 24. The demister orseparator body portion 21 is grooved at 30,if necessary,

where the chimneys are burred against the underside of the tray 12, topermit a tight fit against the tray 12 if used in that way. Where theunderside of tray 12 is finished flush as shown in Figures 7, 9 and 10later to be discussed, the chimney being fastened other than by burringthe end as shown here, groove 30 can be omitted.

Closing the chimney 18'from above, bubble cap 19 includes Within thebody portion 34 three spring clip elements 36 fastened to the cap asbywelding. These clips are spaced circumferentially, at third points forexample, like those of clip 26 described as forming part of theseparator unit, thus permitting cooperative use with the same chimneywhich thus forms the connecting element of the complete combination. Theunsupported end 38 of element 36 is bent to engage the upper side of agroove 24, shown here as that one lowest in the chimney but could be anyone of the group. As shown in Figure 4 the supporting spring clip armsof both the bubble cap and the separator element can use the same groovewithout interference. 'In this figure the engaging ends 38 of springclips 36 are bevelled on the under side and flat on the upper side. Thisshape locks the cap in place resisting lifting pressures yet permitseasy and rapid placement on the chimney. By bevelling the bottom of end38, direct insertion of the cap over the grooved surfaces is permittedavoiding the steps of passage over the smooth area 22 and rotation toengagement as required for the separator element described above. Insidethe bubble cap 19, positioning brackets 40 space the cap horizontallyand vertically from the chimney 18 and relative to tray 12. A ring orhandle 42 is centered outside the cap to permit a turning action andlifting movement for insertion and removal relative to the chimney.

Rotation of the bubble cap 19 through a third turn will remove theengaging ends 38 of clips 36 from grooves 24 to smooth areas 22 of thechimney as shown in Figure 5 phantom lines, and'in Figure 6. The bubblecap is then easily removed. A simple tool similar to a spanner membercan be used to rotate the clips of the sepa- 'ator combination in likefashion to drop them while working above the tray. Or these separatorsmay be removed by rotating the sub-combination by grasping grip 28 androtating as described for removing the bubble cap. Thus the bubble capsand separators in each tier can be removed without assistance above orbelow. Replacement is made by reversing the operation described with theadditional facility of being able to clip the bubble cap withoutrotation as previously described.

The exploded illustration in Figure 6 illustrates the initial steps ofassembly or disassembly which, when taken together with Figure 5 and theabove description, shows one of the advantages of this combination. Thisview of the device compared with Figures 7 to 11, inclusive, willillustrate the combination in contrast with the separate use of thedemister element with other types of chimneys and bubble caps. A workmanin between the trays will have access, on the tray below him, to bubblecaps, and above him to the separator bodies. Discussion of the operationof these elements as shown in these figures will emphasize the placementand removal of these items without additional help above or below.

The above description and discussion is directed to a combination ofelements forming an illustrative embodiment of the invention. Withoutmaterially changing the demister elements, and entirely within the scopeof the letter and spirit of the invention, this portion of thecombination can be adapted for use, to excellent advantage, withexisting equipment. Figures 7 through 11 show such a modification of thedemister bodies 20 -and 21 with the supporting spring clip adapted foruse with existing chimneys in bubble cap assemblies generally. Thesefiguresshow the demister element and support engaging a typical chimney58 in which there are no grooves nor spaced smooth portions describedabove for the combination. No particular form of bubble cap is shown asit does not enter into the support of the demister body as does thechimney. For clarity of understanding, a bubble cap of no particularkind is indicated in phantom line where necessary to complete thesefigures.

As is evident from the illustrations the spring clip 60 varies in lengthas required, being suficiently long to engage an upset portion 62thereof with the top of the chimney in all instances, positioning thedemister body 21 either in contact with the underside of the tray 12(Fig. 7) or spaced therefrom (Figure 9). In these figures the circulardemister element 21 is shown as the element used. With the exception ofFigure 1A where the polygonal form of demister 25 is shown with spacersmounted on the peripheral assemblies, the circular form 21 in Figure 1is otherwise suggested as easier to use. The demister element 20,described as of geometrical section capable of abutting like shapes aspreviously described, is used in specific instances. When so used thestructure would parallel Figure 9 omitting spacer 64 except as in Figure1A, and to be described later. The positions of the separator elementseither adjacent the underside of the tray or spaced therebelow exceptfor the spacer combination of Figures 9, and 11 parallel thosepreviously described relative to Figures 1, 1A, 2 and 3 and need not berepeated here. The spacer can be made of either pervious material suchas demister material as in Figure 9, or of impervious material such asmetal as shown in Figures 10 and 11. When demister material is used, itis evident that the separator area would be extended, as would thetravel path of the gases, and any shape demister element 21 whichextends beyond the tray opening as shown in Figure 9 and spacer 64 couldbe used.

Figures 10 and 11 show a form the combined demister element 21 can takewhen used with an impervious spacer 65. A metallic cup is used here asspacer 65, adapted to form a supporting .ip 67 and spider connection 69across the bottom (Fig. 11). Such construction apertures the cup bottomfor passage of vapors through the supported demister material. A centralsupport 71 provides an area to which a handle or grip 28 is fastened.Upwardly projecting spring clips 60 with upset top portions 62 form theconnecting elements as previously described and are connected as shownin Figure 11 to spider 69. The depth of the metallic cup form of spacer65 is coordinated with the length of clips 69 forming a tight seal withthe underside of tray 14. An insert shaped to fit the cup 65 and allowfor passage of clips 60 forms the demister body noted as number 21. Bymeans of handle or grip 23 the device is readily inserted or removed inchimney 58. Bracket 63 helps position the demister body 21 and cup 65and lends rigidity to clips 60.

From the above it will be evident to those versed in the art that thevapor-liquid contact assembly described may be considered as separatedinto a bubble cap assembly including bubble cap and chimney elements foruse on a perforated tray and a mist barrier element usable either aspart of the combination with the special bubble cap sub-combinationdescribed, or generally with like equipment. As described, the assemblyuses all the included features. When divided into sub-combinations andseparate elements, not all the features are employed. This is especiallytrue of the internal structure of the chimney element. The horizontallygrooved portions with separating smooth areas spaced peripherally of theinterior of the chimney are used by the spring clips of both the bubblecap and the suspended demister in the combination. The horizontalgrooves spaced in the special chimney of this application can be used toregulate the depth of suspension of the mist barrier element and also tovertically position the bubble cap if desired. For securing the bubblecap against pressures and surges in the tower, however, thecentering-elevating bracket 44 of the bubble cap should be fastened atproper elevation in the cap to engage the chimney as shown, thuscooperating with the spring clip arrangement. In all cases the bubblescap rests firmly on the chimney secured by the spring clips engaging thechimney grooves. However, the coordinated operation of the completeassembly of elements, and their separated functions considered assub-combinations and elements, emphasizes the versatility of themechanism and the almost universal application of which it is capable.

The adaptation of a demister body to either the combination or separateuse described has many advantages immediately evident to those versed inthe art. Installation of demister trays presently used, requires fixedsupport facilities and once installed cannot be changed without greatlabor and expense. Maintenance requires complete removal and replacementof the demister layer when any defective area appears. The device heredescribed afiords inexpensive installation. Maintaining the towers usingthese elements is reduced to a one-man job for easy replacement ofdefective parts. Further, the device described can be adjusted with aminimum of labor and expense to meet operational requirements involvingdemister spacing, addition or removal, and provides a wide variety ofarrangements for operational success, not possible with knownstructures.

Iclaim:

l. Mist-eliminating means for use With a bubble cap tray in avapor-liquid contact apparatus in combination with the chimneys mountedin the apertures of said tray and in which each chimney has a pluralityof arcuately spaced grooves vertically arranged to form alternatinggrooved and ungrooved areas inside said chimneys, comprising a springclip with a plurality of arms adapted to extend upwardly into thechimney and circumferentially spaced to contact the grooved andungrooved areas for engaging and disengaging cooperation, a body ofdemister material adapted to intercept the passage of vapors upwardlythrough the bubble cap tray supported by said clip below the chimney,and a grip engaging the arms of the clip below the demister body forrotatably connecting and disconnecting said clip and chimney.

2. The mist-eliminating means of claim 1 further characterized by thebody of demister material adapted to intercept the passage of vaporsbeing shaped to peripherally contact like bodies in a plane below thebubble cap tray forming an unbroken vapor barrier beneath the bubble captray.

3. The mist-eliminating means of claim 1 further characterized by thebody of demister material adapted to intercept the passage of vaporsincluding a demister body of selected peripheral shape spaced below thebubble cap tray, and extensions of demister material supported on saiddemister body and extending the periphery thereof upwardly to operablyengage the underside of the tray.

References Cited in the file of this patent UNITED STATES PATENTS1,200,877 Sable Oct. 10, 1916 1,899,409 Bottoms Feb. 28, 1933 2,055,048Puls Sept. 22, 1936 2,378,952 Rousseau June 26, 1945 2,443,812 AckroydJune 22, 1948 2,510,586 Kelley June 6, 1950 2,525,218 Glitsch Oct. 10,1950 2,778,621 Zimmerman Jan. 22, 1957 2,785,882 Wansink et al Mar. 19,1957 FOREIGN PATENTS 977,279 France Nov. 8, 1950 1,029,074 France Mar.4, 1953

